blob: 0072281d4d977be8e73c9ea32582d3f305baaeed [file] [log] [blame]
// Copyright 2009 The Android Open Source Project
#include <stdio.h>
#include <stdlib.h>
#include <stdarg.h>
#include <string.h>
#include <unistd.h>
#include <fcntl.h>
#include <time.h>
#include <dirent.h>
#include <errno.h>
#include <assert.h>
#include <ctype.h>
#include <utime.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <stdint.h>
#include <cutils/properties.h>
#include <private/android_filesystem_config.h>
#ifndef PATH_MAX
#define PATH_MAX 4096
#endif
// First version.
#define FILE_VERSION_1 0xffff0001
// Introduces backup all option to header.
#define FILE_VERSION_2 0xffff0002
#define FILE_VERSION FILE_VERSION_2
namespace android {
static char nameBuffer[PATH_MAX];
static struct stat statBuffer;
static char copyBuffer[8192];
static char *backupFilePath = NULL;
static uint32_t inputFileVersion;
static int opt_backupAll;
#define SPECIAL_NO_TOUCH 0
#define SPECIAL_NO_BACKUP 1
struct special_dir {
const char* path;
int type;
};
/* Directory paths that we will not backup/restore */
static const struct special_dir SKIP_PATHS[] = {
{ "/data/misc", SPECIAL_NO_TOUCH },
{ "/data/system/batterystats.bin", SPECIAL_NO_TOUCH },
{ "/data/system/location", SPECIAL_NO_TOUCH },
{ "/data/dalvik-cache", SPECIAL_NO_BACKUP },
{ NULL, 0 },
};
/* This is just copied from the shell's built-in wipe command. */
static int wipe (const char *path)
{
DIR *dir;
struct dirent *de;
int ret;
int i;
dir = opendir(path);
if (dir == NULL) {
fprintf (stderr, "Error opendir'ing %s: %s\n",
path, strerror(errno));
return 0;
}
char *filenameOffset;
strcpy(nameBuffer, path);
strcat(nameBuffer, "/");
filenameOffset = nameBuffer + strlen(nameBuffer);
for (;;) {
de = readdir(dir);
if (de == NULL) {
break;
}
if (0 == strcmp(de->d_name, ".")
|| 0 == strcmp(de->d_name, "..")
|| 0 == strcmp(de->d_name, "lost+found")
) {
continue;
}
strcpy(filenameOffset, de->d_name);
bool noBackup = false;
/* See if this is a path we should skip. */
for (i = 0; SKIP_PATHS[i].path; i++) {
if (strcmp(SKIP_PATHS[i].path, nameBuffer) == 0) {
if (opt_backupAll || SKIP_PATHS[i].type == SPECIAL_NO_BACKUP) {
// In this case we didn't back up the directory --
// we do want to wipe its contents, but not the
// directory itself, since the restore file won't
// contain the directory.
noBackup = true;
}
break;
}
}
if (!noBackup && SKIP_PATHS[i].path != NULL) {
// This is a SPECIAL_NO_TOUCH directory.
continue;
}
ret = lstat (nameBuffer, &statBuffer);
if (ret != 0) {
fprintf(stderr, "warning -- stat() error on '%s': %s\n",
nameBuffer, strerror(errno));
continue;
}
if(S_ISDIR(statBuffer.st_mode)) {
char *newpath;
newpath = strdup(nameBuffer);
if (wipe(newpath) == 0) {
free(newpath);
closedir(dir);
return 0;
}
if (!noBackup) {
ret = rmdir(newpath);
if (ret != 0) {
fprintf(stderr, "warning -- rmdir() error on '%s': %s\n",
newpath, strerror(errno));
}
}
free(newpath);
strcpy(nameBuffer, path);
strcat(nameBuffer, "/");
} else {
// Don't delete the backup file
if (backupFilePath && strcmp(backupFilePath, nameBuffer) == 0) {
continue;
}
ret = unlink(nameBuffer);
if (ret != 0) {
fprintf(stderr, "warning -- unlink() error on '%s': %s\n",
nameBuffer, strerror(errno));
}
}
}
closedir(dir);
return 1;
}
static int write_int32(FILE* fh, int32_t val)
{
int res = fwrite(&val, 1, sizeof(val), fh);
if (res != sizeof(val)) {
fprintf(stderr, "unable to write int32 (%d bytes): %s\n", res, strerror(errno));
return 0;
}
return 1;
}
static int write_int64(FILE* fh, int64_t val)
{
int res = fwrite(&val, 1, sizeof(val), fh);
if (res != sizeof(val)) {
fprintf(stderr, "unable to write int64 (%d bytes): %s\n", res, strerror(errno));
return 0;
}
return 1;
}
static int copy_file(FILE* dest, FILE* src, off_t size, const char* destName,
const char* srcName)
{
errno = 0;
off_t origSize = size;
while (size > 0) {
int amt = size > (off_t)sizeof(copyBuffer) ? sizeof(copyBuffer) : (int)size;
int readLen = fread(copyBuffer, 1, amt, src);
if (readLen <= 0) {
if (srcName != NULL) {
fprintf(stderr, "unable to read source (%d of %ld bytes) file '%s': %s\n",
amt, origSize, srcName, errno != 0 ? strerror(errno) : "unexpected EOF");
} else {
fprintf(stderr, "unable to read buffer (%d of %ld bytes): %s\n",
amt, origSize, errno != 0 ? strerror(errno) : "unexpected EOF");
}
return 0;
}
int writeLen = fwrite(copyBuffer, 1, readLen, dest);
if (writeLen != readLen) {
if (destName != NULL) {
fprintf(stderr, "unable to write file (%d of %d bytes) '%s': '%s'\n",
writeLen, readLen, destName, strerror(errno));
} else {
fprintf(stderr, "unable to write buffer (%d of %d bytes): '%s'\n",
writeLen, readLen, strerror(errno));
}
return 0;
}
size -= readLen;
}
return 1;
}
#define TYPE_END 0
#define TYPE_DIR 1
#define TYPE_FILE 2
static int write_header(FILE* fh, int type, const char* path, const struct stat* st)
{
int pathLen = strlen(path);
if (!write_int32(fh, type)) return 0;
if (!write_int32(fh, pathLen)) return 0;
if (fwrite(path, 1, pathLen, fh) != (size_t)pathLen) {
fprintf(stderr, "unable to write: %s\n", strerror(errno));
return 0;
}
if (!write_int32(fh, st->st_uid)) return 0;
if (!write_int32(fh, st->st_gid)) return 0;
if (!write_int32(fh, st->st_mode)) return 0;
if (!write_int64(fh, ((int64_t)st->st_atime)*1000*1000*1000)) return 0;
if (!write_int64(fh, ((int64_t)st->st_mtime)*1000*1000*1000)) return 0;
if (!write_int64(fh, ((int64_t)st->st_ctime)*1000*1000*1000)) return 0;
return 1;
}
static int backup_dir(FILE* fh, const char* srcPath)
{
DIR *dir;
struct dirent *de;
char* fullPath = NULL;
int srcLen = strlen(srcPath);
int result = 1;
int i;
dir = opendir(srcPath);
if (dir == NULL) {
fprintf (stderr, "error opendir'ing '%s': %s\n",
srcPath, strerror(errno));
return 0;
}
for (;;) {
de = readdir(dir);
if (de == NULL) {
break;
}
if (0 == strcmp(de->d_name, ".")
|| 0 == strcmp(de->d_name, "..")
|| 0 == strcmp(de->d_name, "lost+found")
) {
continue;
}
if (fullPath != NULL) {
free(fullPath);
}
fullPath = (char*)malloc(srcLen + strlen(de->d_name) + 2);
strcpy(fullPath, srcPath);
fullPath[srcLen] = '/';
strcpy(fullPath+srcLen+1, de->d_name);
/* See if this is a path we should skip. */
if (!opt_backupAll) {
for (i = 0; SKIP_PATHS[i].path; i++) {
if (strcmp(SKIP_PATHS[i].path, fullPath) == 0) {
break;
}
}
if (SKIP_PATHS[i].path != NULL) {
continue;
}
}
int ret = lstat(fullPath, &statBuffer);
if (ret != 0) {
fprintf(stderr, "stat() error on '%s': %s\n",
fullPath, strerror(errno));
result = 0;
goto done;
}
if(S_ISDIR(statBuffer.st_mode)) {
printf("Saving dir %s...\n", fullPath);
if (write_header(fh, TYPE_DIR, fullPath, &statBuffer) == 0) {
result = 0;
goto done;
}
if (backup_dir(fh, fullPath) == 0) {
result = 0;
goto done;
}
} else if (S_ISREG(statBuffer.st_mode)) {
// Skip the backup file
if (backupFilePath && strcmp(fullPath, backupFilePath) == 0) {
printf("Skipping backup file %s...\n", backupFilePath);
continue;
} else {
printf("Saving file %s...\n", fullPath);
}
if (write_header(fh, TYPE_FILE, fullPath, &statBuffer) == 0) {
result = 0;
goto done;
}
off_t size = statBuffer.st_size;
if (!write_int64(fh, size)) {
result = 0;
goto done;
}
FILE* src = fopen(fullPath, "r");
if (src == NULL) {
fprintf(stderr, "unable to open source file '%s': %s\n",
fullPath, strerror(errno));
result = 0;
goto done;
}
int copyres = copy_file(fh, src, size, NULL, fullPath);
fclose(src);
if (!copyres) {
result = 0;
goto done;
}
}
}
done:
if (fullPath != NULL) {
free(fullPath);
}
closedir(dir);
return result;
}
static int backup_data(const char* destPath)
{
int res = -1;
FILE* fh = fopen(destPath, "w");
if (fh == NULL) {
fprintf(stderr, "unable to open destination '%s': %s\n",
destPath, strerror(errno));
return -1;
}
printf("Backing up /data to %s...\n", destPath);
// The path that shouldn't be backed up
backupFilePath = strdup(destPath);
if (!write_int32(fh, FILE_VERSION)) goto done;
if (!write_int32(fh, opt_backupAll)) goto done;
if (!backup_dir(fh, "/data")) goto done;
if (!write_int32(fh, 0)) goto done;
res = 0;
done:
if (fflush(fh) != 0) {
fprintf(stderr, "error flushing destination '%s': %s\n",
destPath, strerror(errno));
res = -1;
goto donedone;
}
if (fsync(fileno(fh)) != 0) {
fprintf(stderr, "error syncing destination '%s': %s\n",
destPath, strerror(errno));
res = -1;
goto donedone;
}
fclose(fh);
sync();
donedone:
return res;
}
static int32_t read_int32(FILE* fh, int32_t defVal)
{
int32_t val;
if (fread(&val, 1, sizeof(val), fh) != sizeof(val)) {
fprintf(stderr, "unable to read: %s\n", strerror(errno));
return defVal;
}
return val;
}
static int64_t read_int64(FILE* fh, int64_t defVal)
{
int64_t val;
if (fread(&val, 1, sizeof(val), fh) != sizeof(val)) {
fprintf(stderr, "unable to read: %s\n", strerror(errno));
return defVal;
}
return val;
}
static int read_header(FILE* fh, int* type, char** path, struct stat* st)
{
*type = read_int32(fh, -1);
if (*type == TYPE_END) {
return 1;
}
if (*type < 0) {
fprintf(stderr, "bad token %d in restore file\n", *type);
return 0;
}
int32_t pathLen = read_int32(fh, -1);
if (pathLen <= 0) {
fprintf(stderr, "bad path length %d in restore file\n", pathLen);
return 0;
}
char* readPath = (char*)malloc(pathLen+1);
if (fread(readPath, 1, pathLen, fh) != (size_t)pathLen) {
fprintf(stderr, "truncated path in restore file\n");
free(readPath);
return 0;
}
readPath[pathLen] = 0;
*path = readPath;
st->st_uid = read_int32(fh, -1);
if (st->st_uid == (uid_t)-1) {
fprintf(stderr, "bad uid in restore file at '%s'\n", readPath);
return 0;
}
st->st_gid = read_int32(fh, -1);
if (st->st_gid == (gid_t)-1) {
fprintf(stderr, "bad gid in restore file at '%s'\n", readPath);
return 0;
}
st->st_mode = read_int32(fh, -1);
if (st->st_mode == (mode_t)-1) {
fprintf(stderr, "bad mode in restore file at '%s'\n", readPath);
return 0;
}
int64_t ltime = read_int64(fh, -1);
if (ltime < 0) {
fprintf(stderr, "bad atime in restore file at '%s'\n", readPath);
return 0;
}
st->st_atime = (time_t)(ltime/1000/1000/1000);
ltime = read_int64(fh, -1);
if (ltime < 0) {
fprintf(stderr, "bad mtime in restore file at '%s'\n", readPath);
return 0;
}
st->st_mtime = (time_t)(ltime/1000/1000/1000);
ltime = read_int64(fh, -1);
if (ltime < 0) {
fprintf(stderr, "bad ctime in restore file at '%s'\n", readPath);
return 0;
}
st->st_ctime = (time_t)(ltime/1000/1000/1000);
st->st_mode &= (S_IRWXU|S_IRWXG|S_IRWXO);
return 1;
}
static int restore_data(const char* srcPath)
{
int res = -1;
FILE* fh = fopen(srcPath, "r");
if (fh == NULL) {
fprintf(stderr, "Unable to open source '%s': %s\n",
srcPath, strerror(errno));
return -1;
}
inputFileVersion = read_int32(fh, 0);
if (inputFileVersion < FILE_VERSION_1 || inputFileVersion > FILE_VERSION) {
fprintf(stderr, "Restore file has bad version: 0x%x\n", inputFileVersion);
goto done;
}
if (inputFileVersion >= FILE_VERSION_2) {
opt_backupAll = read_int32(fh, 0);
} else {
opt_backupAll = 0;
}
// The path that shouldn't be deleted
backupFilePath = strdup(srcPath);
printf("Wiping contents of /data...\n");
if (!wipe("/data")) {
goto done;
}
printf("Restoring from %s to /data...\n", srcPath);
while (1) {
int type;
char* path = NULL;
if (read_header(fh, &type, &path, &statBuffer) == 0) {
goto done;
}
if (type == 0) {
break;
}
const char* typeName = "?";
if (type == TYPE_DIR) {
typeName = "dir";
printf("Restoring dir %s...\n", path);
if (mkdir(path, statBuffer.st_mode) != 0) {
if (errno != EEXIST) {
fprintf(stderr, "unable to create directory '%s': %s\n",
path, strerror(errno));
free(path);
goto done;
}
}
} else if (type == TYPE_FILE) {
typeName = "file";
off_t size = read_int64(fh, -1);
if (size < 0) {
fprintf(stderr, "bad file size %ld in restore file\n", size);
free(path);
goto done;
}
printf("Restoring file %s...\n", path);
FILE* dest = fopen(path, "w");
if (dest == NULL) {
fprintf(stderr, "unable to open destination file '%s': %s\n",
path, strerror(errno));
free(path);
goto done;
}
int copyres = copy_file(dest, fh, size, path, NULL);
fclose(dest);
if (!copyres) {
free(path);
goto done;
}
} else {
fprintf(stderr, "unknown node type %d\n", type);
goto done;
}
// Do this even for directories, since the dir may have already existed
// so we need to make sure it gets the correct mode.
if (chmod(path, statBuffer.st_mode&(S_IRWXU|S_IRWXG|S_IRWXO)) != 0) {
fprintf(stderr, "unable to chmod destination %s '%s' to 0x%x: %s\n",
typeName, path, statBuffer.st_mode, strerror(errno));
free(path);
goto done;
}
if (chown(path, statBuffer.st_uid, statBuffer.st_gid) != 0) {
fprintf(stderr, "unable to chown destination %s '%s' to uid %d / gid %d: %s\n",
typeName, path, (int)statBuffer.st_uid, (int)statBuffer.st_gid, strerror(errno));
free(path);
goto done;
}
struct utimbuf timbuf;
timbuf.actime = statBuffer.st_atime;
timbuf.modtime = statBuffer.st_mtime;
if (utime(path, &timbuf) != 0) {
fprintf(stderr, "unable to utime destination %s '%s': %s\n",
typeName, path, strerror(errno));
free(path);
goto done;
}
free(path);
}
res = 0;
done:
fclose(fh);
return res;
}
static void show_help(const char *cmd)
{
fprintf(stderr,"Usage: %s COMMAND [options] [backup-file-path]\n", cmd);
fprintf(stderr, "commands are:\n"
" help Show this help text.\n"
" backup Perform a backup of /data.\n"
" restore Perform a restore of /data.\n");
fprintf(stderr, "options include:\n"
" -h Show this help text.\n"
" -a Backup all files.\n");
fprintf(stderr, "\n backup-file-path Defaults to /sdcard/backup.dat .\n"
" On devices that emulate the sdcard, you will need to\n"
" explicitly specify the directory it is mapped to,\n"
" to avoid recursive backup or deletion of the backup file\n"
" during restore.\n\n"
" Eg. /data/media/0/backup.dat\n");
fprintf(stderr, "\nThe %s command allows you to perform low-level\n"
"backup and restore of the /data partition. This is\n"
"where all user data is kept, allowing for a fairly\n"
"complete restore of a device's state. Note that\n"
"because this is low-level, it will only work across\n"
"builds of the same (or very similar) device software.\n",
cmd);
}
} /* namespace android */
int main (int argc, char **argv)
{
int restore = 0;
if (getuid() != AID_ROOT) {
fprintf(stderr, "error -- %s must run as root\n", argv[0]);
exit(-1);
}
if (argc < 2) {
fprintf(stderr, "No command specified.\n");
android::show_help(argv[0]);
exit(-1);
}
if (0 == strcmp(argv[1], "restore")) {
restore = 1;
} else if (0 == strcmp(argv[1], "help")) {
android::show_help(argv[0]);
exit(0);
} else if (0 != strcmp(argv[1], "backup")) {
fprintf(stderr, "Unknown command: %s\n", argv[1]);
android::show_help(argv[0]);
exit(-1);
}
android::opt_backupAll = 0;
optind = 2;
for (;;) {
int ret;
ret = getopt(argc, argv, "ah");
if (ret < 0) {
break;
}
switch(ret) {
case 'a':
android::opt_backupAll = 1;
if (restore) fprintf(stderr, "Warning: -a option ignored on restore\n");
break;
case 'h':
android::show_help(argv[0]);
exit(0);
break;
default:
fprintf(stderr,"Unrecognized Option\n");
android::show_help(argv[0]);
exit(-1);
break;
}
}
const char* backupFile = "/sdcard/backup.dat";
if (argc > optind) {
backupFile = argv[optind];
optind++;
if (argc != optind) {
fprintf(stderr, "Too many arguments\n");
android::show_help(argv[0]);
exit(-1);
}
}
printf("Stopping system...\n");
property_set("ctl.stop", "runtime");
property_set("ctl.stop", "zygote");
sleep(1);
int res;
if (restore) {
res = android::restore_data(backupFile);
if (res != 0) {
// Don't restart system, since the data partition is hosed.
return res;
}
printf("Restore complete! Restarting system, cross your fingers...\n");
} else {
res = android::backup_data(backupFile);
if (res == 0) {
printf("Backup complete! Restarting system...\n");
} else {
printf("Restarting system...\n");
}
}
property_set("ctl.start", "zygote");
property_set("ctl.start", "runtime");
}